Chronic Kidney Disease

Call local emergency services for severe breathlessness, chest pain, confusion, a seizure, fainting, severe weakness with palpitations, or rapidly worsening swelling. Very little urine, persistent vomiting or dehydration, fever with feeling very unwell, or a sudden deterioration needs prompt medical assessment because acute kidney injury, severe potassium disturbance, fluid in the lungs or infection may require urgent treatment. Do not delay care to try a home remedy.

What is chronic kidney disease?

Chronic kidney disease (CKD) means an abnormality of kidney structure or function that has health implications and is present for at least three months. It covers a wide range, from early disease with preserved filtration to kidney failure. CKD is not the same as sudden acute kidney injury, and it does not mean that complete kidney failure is inevitable. Some causes can be treated and many people remain stable for years, although established scarring may not reverse.

Kidneys remove waste and excess fluid, balance electrolytes and acid, help control blood pressure, signal red-blood-cell production and support bone and mineral health. CKD can therefore affect the heart, blood, bones, nutrition and fluid balance as well as filtration.

Causes and who should be tested

Diabetes and high blood pressure are common causes in adults, but CKD also occurs with glomerular and autoimmune disease, inherited conditions such as polycystic kidney disease, structural obstruction, recurrent kidney infections, repeated stones, medicines or toxins, and previous acute kidney injury. Risk is influenced by several factors and is not a person’s fault.

Testing is particularly important for people with diabetes, hypertension, cardiovascular disease, previous acute kidney injury, urinary obstruction, recurrent stones or pyelonephritis, systemic or hereditary disease, or a family history of kidney failure. A clinician decides the interval from the condition and previous results. Age or body size alone does not establish CKD.

Symptoms and diagnosis

Early CKD commonly causes no symptoms, so blood and urine tests are the only reliable way to detect it. With more advanced disease, possible symptoms include ankle or facial swelling, fatigue, nausea, reduced appetite, itching, sleep or concentration problems, breathlessness and changes in urine. These symptoms have many causes and cannot diagnose CKD by themselves.

A serum creatinine result is used to estimate glomerular filtration rate (eGFR); a urine albumin-to-creatinine ratio (ACR) measures albumin leakage. Both are needed because filtration and albuminuria independently predict kidney and cardiovascular risk. An abnormal result is usually repeated after acute illness has been considered. CKD requires persistence beyond three months or other clear evidence of chronicity.

Clinicians classify CKD by cause, GFR category G1–G5 and albuminuria category A1–A3. The numbers are interpreted in context because creatinine-based estimates can be less reliable during acute illness or with unusual muscle mass; cystatin C may help in selected cases. Urine microscopy, blood tests and ultrasound are chosen according to the suspected cause and complications. CT, MRI or kidney biopsy is used selectively when it can clarify diagnosis or change treatment, not as a routine menu for everyone.

Protecting kidney and heart health

Care aims to treat the cause, slow loss of function, reduce cardiovascular and kidney-failure risk and manage symptoms. Blood-pressure, diabetes and lipid treatment is individualised. An ACE inhibitor or angiotensin-receptor blocker may provide particular kidney benefit when albuminuria is present, but creatinine and potassium require monitoring. These two drug classes should not be combined, and pregnancy or pregnancy planning requires an urgent medicine review.

SGLT2 inhibitors reduce kidney and cardiovascular risk in eligible CKD groups, including some people without diabetes. They are prescribed with advice about side effects and temporary withholding during prolonged fasting, surgery or critical illness. Selected people with type 2 diabetes may also benefit from a GLP-1 receptor agonist or finerenone, with kidney-function and potassium checks where appropriate. Do not start, combine, pause or stop these medicines without the treating clinician’s plan.

A diuretic may treat fluid overload but needs blood-pressure, electrolyte and kidney monitoring. Anaemia treatment follows assessment of haemoglobin, iron status and other causes; iron or an erythropoiesis-stimulating medicine is used selectively, while transfusion is reserved for a specific clinical need. Calcium, phosphate, parathyroid hormone and vitamin D are assessed according to CKD stage. Routine calcium or vitamin D supplements can be harmful and are not a universal bone treatment.

Food, medicines and monitoring

A renal dietitian can tailor sodium, protein, potassium, phosphate, energy and fluid advice to CKD stage, medicines and laboratory results. Avoid both high-protein diets and unnecessary restriction that causes malnutrition. Potassium or fluid limits are not required for everyone. Bring all prescription medicines, pain relievers and supplements to review; non-steroidal anti-inflammatory drugs and some herbal products can harm kidneys or interact with treatment. Never stop a necessary medicine based only on an online list.

Follow-up commonly tracks eGFR, ACR, blood pressure, potassium and stage-specific complications. Nephrology referral may be needed for high predicted kidney-failure risk, rapid decline, severe albuminuria with blood in urine, resistant hypertension, obstruction or suspected rare or genetic disease. New illness, dehydration or contrast procedures may also require a medication and kidney-function plan.

When kidney function becomes very low

Planning should start before a crisis. Options include haemodialysis, peritoneal dialysis, kidney transplantation from a living or deceased donor, and comprehensive conservative kidney management focused on symptoms and quality of life without dialysis or transplant. Each is a legitimate pathway with different burdens and benefits. The decision should reflect health, goals, support and informed preference.

Dialysis is started because of symptoms, persistent biochemical problems, uncontrolled fluid overload or other clinical needs—not one eGFR number alone. A transplant usually leaves the person’s own kidneys in place and requires lifelong anti-rejection treatment; it treats kidney failure but is not a cure. Shared planning can include family, a kidney team and supportive or palliative care.

Outlook and risk reduction

CKD can raise the risks of cardiovascular disease, stroke, acute kidney injury, anaemia, mineral and bone disorder, acidosis, high potassium, infection, malnutrition and kidney failure. Timely detection allows protective care but cannot guarantee a particular outcome. Use medicines as directed, avoid tobacco, stay active within your ability and keep diabetes, blood pressure and cardiovascular follow-up. Many inherited, autoimmune and structural causes are not preventable; the practical goal is safer treatment and lower risk, not blame.